The protagonist forces a love interest who is already in a relationship with a third party into a physical relationship, and the love interest comes to like it over time, thus either cheating or breaking up with their original partner. If the protagonist is the one having their partner seduced, use 'Netorare' instead. If there's no evolution from unwillingness to infatuation, use 'Adultery' instead.
Office worker Leon is reincarnated into a particularly punishing dating sim video game, where women reign supreme and only beautiful men have a seat at the table. But Leon has a secret weapon: he remembers everything from his past life, which includes a complete playthrough of the very game in which he is now trapped. Watch Leon spark a revolution to change this new world in order to fulfill his ultimate desire…of living a quiet, easy life in the countryside!